There are many friendly people and organizations who put together binary packages of curl and libcurl and make them available for download.
Many operating systems offer a "package repository" that is populated with software packages for you to install. From the curl download page you can also follow links to plain binary packages for popular operating systems.
curl and libcurl have been around for a very long time and most Linux distributions, BSD versions and other *nix versions have package repositories that allow you to install curl packages.
The most common ones are described below.
apt is a tool to install prebuilt packages on Debian Linux and Ubuntu Linux
distributions and derivates.
To install the curl command-line tool, you usually just
apt install curl
…and that then makes sure the dependencies are installed and usually libcurl is then also installed as an individual package.
If you want to build applications against libcurl, you need a development package installed to get the include headers and some additional documentation, etc. You can then select a libcurl with the TLS backend you prefer:
apt install libcurl4-openssl-dev
or
apt install libcurl4-nss-dev
or
apt install libcurl4-gnutls-dev
With Redhat Linux and CentOS Linux derivates, you use yum to install
packages. Install the command-line tool with:
yum install curl
You install the libcurl development package (with include files and some docs, etc.) with this:
yum install curl-devel
(The Redhat family of Linux systems usually ship curl built to use NSS as TLS backend.)
Nix is a package manager default to the NixOS distribution, but it can also be used on any Linux distribution.
In order to install command-line tool:
nix-env -i curl
Homebrew is an OSX package manager. It does not come by default, but one can install it easily.
To install the command-line tool:
brew install curl
TBD
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